In a large enameled cast-iron casserole, heat 1 tablespoon of the olive oil. Season the turkey with salt and pepper and cook over moderately high heat until richly browned all over, about 8 minutes. Transfer the turkey to a plate.

Add the remaining 1 tablespoon of oil to the casserole along with the garlic, diced onion, oregano and jalapeno and cook over moderate heat, stirring, until the onion is softened, about 8 minutes. Add the tomato, ancho and cinnamon stick and cook, stirring, until the tomato releases its juices.

Return the turkey to the casserole, add the beer and water and bring to a boil. Cover and simmer over low heat, turning once, until the turkey thighs are tender, about 1 hour. Transfer the turkey to a plate and let cool. Discard the oregano sprig and cinnamon stick and boil the sauce over high heat until reduced to 1/4 cup, about 12 minutes.

Preheat the oven to 350 degrees . Wrap the tortillas in foil and bake for about 8 minutes, until softened and heated through. Remove the turkey meat and shred it. Transfer the sauce to a food processor and puree. Return the sauce to the pot and stir in the shredded turkey. Season with salt and pepper. Spoon the turkey onto the tortillas. Top with minced onion, sesame seeds and cilantro sprigs and serve.

The shredded braised turkey can be refrigerated in the sauce for up to 2 days. Reheat gently.